Neurological investigations in 23 cases of pyrethroid intoxication reported to the German Federal Health Office

In 1993, 64 cases of chronic pyrethroid intoxication were reported to the Federal Health Office in Germany. Shortly afterwards the media spoke of thousands of cases of pyrethroid intoxication in homes. 23 of the persons reported were examined in a neurological department on an inpatient basis using clinical neurological, neuroradiological and laboratory investigations, including the examination of pyrethroid values in blood and urine. The pyrethroid exposure involved carpets, moth killers, pesticide sprays and wood preservatives. Nine of the cases presented with severe somatic or psychiatric disorders with completely different clinical diagnoses, such as pituitary tumor, radiogenic lumbosacral plexus paralysis, Guillain- Barré syndrome, spinal muscular atrophy, with no plausible relationship to exposure. Eight cases presented with multiple chemical sensitivity syndrome (MCS) and normal somatic findings. In six of the cases, a causal link between acute complaints and pyrethroid exposure could be established or not ruled out. There was, however, not a single case in which evidence for irreversible PNS or CNS lesions could be found.